<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
        "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <head>
        <title>hr</title>
    </head>
    <body>

        a
        <!--分割线 -->
        <hr />
        b
        c


    </body>
</html>